independent variable

Review of

Chapter 1Inquiry

SG Question #1Given an experiment, be able to pick out the independent variable, dependent variable, control, constants, and the hypothesis.

• Independent variable – the variable we are TESTING (or what changes between experimental setups)

• Dependent variable – the variable we are MEASURING (whatever measurement we take)

• Control – the “normal” setup we compare the other setups back t o

• Constants – things that stay the same between the setups

• Hypothesis – an educated guess as to what you THINK will happen in an experiment

SG Question #1Practice

Krusty Krabs Breath Mints

Mr. Krabs created a secret ingredient for a breath mint that he thinks will “cure” the bad breath people

get from eating crabby patties at the Krusty Krab. He asked 100 customers with a history of bad breath

to try his new breath mint. He had fifty customers (Group A) eat a breath mint after they finished

eating a crabby patty. The other fifty (Group B) also received a breath mint after they finished the

sandwich, however, it was just a regular breath mint and did not have the secret ingredient. Both

groups were told that they were getting the breath mint that would cure their bad breath. Two hours

after eating the crabby patties, thirty customers in Group A and ten customers in Group B reported

having better breath than they normally had after eating crabby patties.

1. Which people are in the control group?2. What is the independent variable?3. What is the dependent variable?4. What should Mr. Krabs’ conclusion be?5. Why do you think 10 people in group B reported fresher breath?


SpongeBob Clean Pants

SpongeBob noticed that his favorite pants were not as clean as they used to be. His friend Sandy told

him that he should try using Clean-O detergent, a new brand of laundry soap she found at Sail-Mart.

SpongeBob made sure to wash one pair of pants in plain water and another pair in water with the

Clean-O detergent. After washing both pairs of pants a total of three times, the pants washed in the

Clean-O detergent did not appear to be any cleaner than the pants washed in plain water.

1. What was the problem SpongeBob wanted to investigate?

2. What is the independent variable?

3. What is the dependent variable?

4. What should Sponge Bob’s conclusion be?


Squidward’s Symphony

Squidward loves playing his clarinet and believes it attracts more jellyfish than any other instrument he

has played. In order to test his hypothesis, Squidward played a song on his clarinet for a total of 5

minutes and counted the number of jellyfish he saw in his front

yard. He played the song a total of 3 times on his clarinet and

repeated the experiment using a flute and a guitar. He also

recorded the number of jellyfish he observed when he was not

playing an instrument. The results are shown in the chart.



3. What should Squidward’s conclusion be?

4. Are the results reliable? Why or why not?


Super Bubbles

Patrick and SpongeBob love to blow bubbles! Patrick found some Super Bubble Soap at Sail-Mart. The ads claim that Super Bubble Soap will produce bubbles that are twice as big as bubbles made with regular bubble soap. Patrick and SpongeBob made up two samples of bubble solution.

One sample was made with 5 oz. of Super Bubble Soap and 5 oz. of water, while the other was made with the same amount of water and 5 oz. of regular bubble soap. Patrick and SpongeBob used their favorite bubble wands to blow 10 different bubbles and did their best to measure the diameter of each one. The results are shown in the chart

1. What did the Super Bubble ads claim?



4. What should their conclusion be?

5. Are the results reliable? Why or why not?

SG Question #2

Line – shows trends over time (ex: temperature change over the course of 1 hour)Bar – compares quantities (ex: what color people prefer)Pie – shows percentages out of 100% (ex: what percent of people study vs. what percent of those who don’t)

Know the three types of graphs we learned about – line, bar, pie – and know what each would be used for.


For each of the following scenarios, tell what type of graph is the MOST appropriate.

1. A student wants to keep track of her weight loss over time.

2. Graphing which ride people like best at a carnival.

3. Graphing which team of 5 scored the most points in a quiz bowl.

4. Graphing percent of exports from different countries coming into the U.S.

5. Amount of money spent per student over the last 10 years.

SG Question #3Know the types of lab glassware we studied – the beaker, Ehrlenmeyer flask, and graduated cylinder – and what each is used for.

What is this?What is it used for?

SG Question #4Know the difference between science and technology and examples of each.

• A scientific investigation seeks to solve a problem using the experimental process

• The technological design process is used to design products that people can use, using the principles of science.


For each of the following, tell whether it is science or technology.

1. Studying how the brain reacts to a new drug.

2. Creating a new drug to be taken by patients.

3. A person studies fossils in rocks.

4. Studying drinking water to see what germs are living in it.

5. Inventing a machine that decreases greenhouse gases in the atmosphere.

6. Testing which paper towel is the most absorbent.

SG Question #5Know what the gram, liter, second, and meter are measures of (i.e. volume, length, time, mass)

Gram = ?

Liter = ?

Meter = ?

Second = ?

milliliter = ?

Centigram = ?

Kilometer = ?

SG Question #6Know about how long a meter, centimeter, millimeter, and kilometer are and, given an item, which would be the most appropriate unit of measure to use.

Which unit from above would be MOST appropriate to measure the following?

• From Spartanburg to Greenville• The length of a drinking straw• The width of this classroom• The width of a human hair• The width of a dog’s tongue• The length of a microscope slide• The size of a period .

SG Question #7Be able to do simple metric conversions using the King Henry method. The only prefixes you need to know are centi-, milli-, and kilo-.

What numbers are associated with the following?

• Centi – • Milli – • Kilo –

SG Question #7Be able to do simple metric conversions using the King Henry method. The only prefixes you need to know are centi-, milli-, and kilo-.

King Henry Died By Drinking Chocolate Milk

• What are the “base” units?

Do the following metric conversions:

• 57.9 mm to m• 1.2 kiloliters to cL• 0.0067 grams to kg• 3 cg to mg

SG Question #8Know the difference between accuracy and precision.

• What is accuracy?

• What is precision?


The manufacturer claims each pack contains 20 lollipops.

Accuracy: a sample of packets have 19,20,22,18,21,19,21 lollies. The average is 20. Accurate to the claim.

Precision: a sample of packets have 18,17,17,17,18,18,17 lollies. Not accurate to the claim, but the values are constant.


Doing an experiment, with five trials, the end results of the five trials for whatever is being tested are:

35kg 36kg 33kg 35kg 36kgThe actual value (as found in a scientific data book) is meant to be 42kg.

From the results, the average value is 35kg. This is not at all accurate since the actual value should be 42kg. The results are precise however, since they do not vary from each other.

SG Question #9Know the parts of the microscope and what the function of each part is.

SG Question #9

Answers:

a. Oculars – look through; multiply x 10c. Objective lenses – 4x, 10x, 40x magnificationsf. Diaphragm – regulates the amount of lightg. Light sourceh. Arm – use this to carry withi. Coarse adjustment knob – focuses specimenj. Fine adjustment knob – sharpens imagek. Stage adjustment knob – moves slide aroundl. Base

SG Question #10

Know the difference between an observation and an inference.

Label each of the following as either an observation or an inference:

• The dog is hairy.• The dog’s hair smells.• The bubbles are caused by oxygen.• The table measures 31.2 inches.• The horse is tired because he is laying down.• The mixed up animal tracks means the animals fought.

I’m expecting GREAT things tomorrow – please study your

study guide!

independent variable – the variable we are testing (or what changes between experimental setups)...

Documents

new breath mint

fresher breath

better breath

regular breath mint

bad breath people

history of bad breath

customers group